AB1073 HIGH INCIDENCE OF VIRUSES INFECTION IN CONNECTIVE TISSUE DISEASES PATIENTS
Authors: R. Su, B. C. LI, H. Yan, C. Wang
Journal: Annals of the Rheumatic Diseases (2022)

Background Connective tissue diseases (CTDs) are a group of diseases with a variety of clinical manifestations. The main drug was glucocorticoids and immunosuppressive drugs, but the results are not satisfactory and the side effects are obvious, increased the incidence of infection, especially opportunistic infections. Infections becomes important causes of morbidity and mortality in CTD patients. Objectives To evaluate the incidence of infection in CTD patients who were clinically considered for co-infection by a combination of metagenomic next-generation sequencing (mNGS) and conventional diagnostic testing methods. Methods We analyzed 126 connective tissue diseases (CTD)patients with suspected infections admitted to The Second Hospital of Shanxi Medical University. All patients with CTD were diagnosed according to relevant diagnostic criteria, including 34 systemic lupus erythematosus (SLE), 24 dermatomyositis and polymyositis (DM/PM), 19 rheumatoid arthritis (RA), 10 undifferentiated connective tissue disease(UCTD),16 Sjogren syndrome (SS), 5 mixed connective tissue disease (MCTD), 5 ANCA associated systemtc vasculitis (AAV), 5 adult onset Stillystemtc isease disease(tic criteria, including 34nfections admitted to The Second Hospital of Shanxi (TA), 1 systemic sclerosis (SSC), 1retroperitoneal fibrosis (RPF). All enrolled patients were tested for conventional diagnostic testing methods(CDT) and mNGS. Results Among the 126 patients with CTD who were clinically considered for co-infection, 31 patients were negative for mNGS, and pathogens were detected in 99 of them. In our results, the mNGS and CDT were both positive for pathogens detection in 28 individuals.Of both positive individuals, 2 cases were perfect matches,12 cases were partly matched, 14 cases were totally mismatched. A total of 23 cases were negative for both mNGS and CDT. 70 cases were positive for mNGS only.There were only 5 cases positive for pathogens detection by CDT only. In addition, the results of mNGS showed that 131 patients were virus-positive(54%), 78 patients were prokaryotes-positive (37%) inculding bacteria, mycoplasma and 14 patients were eukaryotes-positive (9%). Of course, someones have mixed infections among these patinets some of these patients, with two or more pathogens. In the mixed infection, 5 cases have no viruses infection, 38 cases with virus infection, including 20 cases of bacteria and viruses infection, 4 cases of bacteria,fungi and viruses infection, 9 cases of viruses mixed infection, 1 case of bacteria,viruses,fungi and mycoplasma infection, 1 case of bacteria,viruses and mycoplasma infection, 1 case of viruses and mycoplasma infection, 1 case of viruses and fungi infection. According to the results, viruses were the most common pathogens identified, followed by prokaryotes and eukaryotes. It is noteworthy that the incidence of Human gammaherpesvirus 4(EBV), Human betaherpesvirus 5(CMV) and Human alphaherpesvirus 1 are more common in virus-positive. The most frequently detected prokaryotes were Acinetobacter baumannii, Mycobacterium tuberculosis complex, followed by Staphylococcus aureus, Prevotella melaninogenica,Staphylococcus homini and Helicobacter pylori. The major pathogens were Pneumocystis jirovecii and Candida albicans among eukaryotes-positive individuals. Conclusion As a complementary approach to conventional methods, mNGS could help improving the identification of infection in CTD patients.The incidence of viral infection is high in patients with connective tissue disease and close attention should be paid to it in clinical works. Figure 1. A. Comparison of test results between mNGS and conventional diagnostic testing methods(CDT) in CTD patients. B. The classification of mixed infections with or without viruses infection detected by mNGS and conventional diagnostic testing methods(CDT). Figure 2. Distribution of pathogens detected by mNGS. A. Type distribution of pathogens identified by mNGS. Species distribution of viruses of B.viruses, C.Prokayote, D. Eucayon detected by mNGS. Disclosure of Interests None declared